The embodiment relates to a light emitting device.
A light emitting device (LED) includes a p-n junction diode having a characteristic of converting electric energy into light energy. The p-n junction diode can be formed by combining group III and group V elements of the periodic table. The LED can represent various colors by adjusting the compositional ratio of compound semiconductors.
When forward voltage is applied to the LED, electrons of an n-type layer are combined with holes of a p-type layer, so that energy corresponding to an energy gap between a conduction band and a valance band may be generated.
In particular, blue, green, red and UV light emitting devices employing the nitride semiconductor have already been developed and extensively used.